A quick guide to make money:
-Take explorer mission and walk to the west till you almost reach the black zone
-You'll get 200 chips
-Walk back and take mission again.
-Repeat

Then after you have 2000-5000 chips, go take the slots mission.
-Go to James tower (purple building) and plays slots, bet 5 or 10 on 9 lines.
-Keep betting until you accumulated 300 won chips
-Go back to the mission NPC
-Collect reward
-Take mission again
-Repeat

It might go up and down, but eventually you make more money than you lost. If you happen to have bad luck and run out of chips, just do the explorer mission again a few times.

After you made enough money, buy land and build casino.
If you manage your casino well, you could net profit about 200+ per hour.

Good luck and have fun!

It is important to remember that this is still an early private beta. The bank is a future planned feature and is just for looks at the moment. Over the coming weeks we'll be adding many more missions to do. You can also make money from slots, poker and the tycoon aspect of running your own casino.